1. Technical Field
The present invention relates to a semiconductor integrated circuit, and more particularly, to a circuit for rupturing an anti-fuse.
2. Related Art
A semiconductor integrated circuit undergoes a test, and setting values of an internal circuit are determined according to the test result. The semiconductor integrated circuit includes a fuse circuit for fixing the setting values (a delay value, a voltage level of an internal voltage, a redundancy address, etc.) of the internal circuit according to the test result.
In general, in the fuse circuit, it is determined whether to cut a fuse associated with a test when changing the setting values according to the test result. In this regard, a method of cutting a fuse using a laser has been adopted. However, in the method of cutting a fuse using a laser, since a fuse cutting process should be included in a procedure for manufacturing a semiconductor integrated circuit, a manufacturing time is lengthened.
Currently, a method of rupturing a fuse by applying a high voltage to the fuse has been adopted. Nevertheless, the method of rupturing a fuse by applying a high voltage to the fuse has a disadvantage in that fuse rupture reliability is likely to be degraded.
In order to improve fuse rupture reliability, a method of rupturing fuses by applying a high voltage to a plurality of fuses as shown in FIG. 1 has been suggested.
Referring to FIG. 1, a conventional semiconductor integrated circuit includes first to third anti-fuse setting units 10, 20 and 30.
The first anti-fuse setting unit 10 includes a first rupture determining section 11, a first rupture instructing section 12, a first anti-fuse section 13, a first blocking section 14, and a first sensing section 15.
The first rupture determining section 11 determines whether to rupture a fuse, in response a fuse rupture command signal BST and an address ADD, and outputs a determination result as a first rupture determination signal RUP_dec1.
The first rupture instructing section 12 generates a first rupture instructing pulse signal RUP_comp1 in response to the first rupture determination signal RUP_dec1.
The first anti-fuse section 13 ruptures an anti-fuse in response to the first rupture instructing pulse signal RUP_comp1, and generates rupture information of the fuse as a first fuse information signal F_inf1. The first anti-fuse section 13 ruptures an anti-fuse by simultaneously applying a high voltage (for example, a positive pumping voltage) and a low voltage (for example, a negative pumping voltage) to both ends of the anti-fuse during the enable period of the first rupture instructing pulse signal RUP_comp1.
In response to a rupture period blocking signal RUP_cut, the first blocking section 14 prevents the high voltage used during the period in which the first anti-fuse section 13 ruptures the anti-fuse, from being transferred to the first sensing section 15.
The first sensing section 15 senses the first fuse information signal F_inf1 transferred through the first blocking section 14 from the first anti-fuse section 13, and outputs a sensing result as a first output signal OUT1.
The second anti-fuse setting unit 20 includes a second rupture determining section 21, a second rupture instructing section 22, a second anti-fuse section 23, a second blocking section 24, and a second sensing section 25.
The second rupture determining section 21 determines whether to rupture a fuse, in response to the fuse rupture command signal BST and the address ADD, and outputs a determination result as a second rupture determination signal RUP_dec2.
The second rupture instructing section 22 generates a second rupture instructing pulse signal RUP_comp2 in response to the second rupture determination signal RUP_dec2.
The second anti-fuse section 23 ruptures an anti-fuse in response to the second rupture instructing pulse signal RUP_comp2, and generates the rupture information of the fuse as a second fuse information signal F_inf2. The second anti-fuse section 23 ruptures an anti-fuse by simultaneously applying a high voltage (for example, a positive pumping voltage) and a low voltage (for example, a negative pumping voltage) to both ends of the anti-fuse during the enable period of the second rupture instructing pulse signal RUP_comp2.
In response to the rupture period blocking signal RUP_cut, the second blocking section 24 prevents the high voltage used during the period in which the second anti-fuse section 23 ruptures the anti-fuse from being transferred to the second sensing section 25.
The second sensing section 25 senses the second fuse information signal F_inf2 transferred through the second blocking section 24 from the second anti-fuse section 23, and outputs a sensing result as a second output signal OUT2.
The third anti-fuse setting unit 30 includes a third rupture determining section 31, a third rupture instructing section 32, a third anti-fuse section 33, a third blocking section 34, and a third sensing section 35.
The third rupture determining section 31 determines whether to rupture a fuse, in response to the fuse rupture command signal BST and the address ADD, and outputs a determination result as a third rupture determination signal RUP_dec3.
The third rupture instructing section 32 generates a third rupture instructing pulse signal RUP_comp3 in response to the third rupture determination signal RUP_dec3.
The third anti-fuse section 33 ruptures a fuse in response to the third rupture instructing pulse signal RUP_comp3, and generates the rupture information of the fuse as a third fuse information signal F_inf3. The third anti-fuse section 33 ruptures an anti-fuse by simultaneously applying a high voltage and a low voltage to both ends of the anti-fuse during the enable period of the third rupture instructing pulse signal RUP_comp3.
In response to the rupture period blocking signal RUP_cut, the third blocking section 34 prevents the high voltage used during the period in which the third anti-fuse section 33 ruptures the anti-fuse from being transferred to the third sensing section 35.
The third sensing section 35 senses the third fuse information signal F_inf3 transferred through the third blocking section 34 from the third anti-fuse section 33, and outputs a sensing result as a third output signal OUT3.
As the above descriptions show, in the conventional semiconductor integrated circuit for rupturing an anti-fuse in order to rupture a plurality of anti-fuses, there needs to be the same number of anti-fuse setting units as anti-fuses. Because the plurality of anti-fuse setting units have the same configuration are needed, an area that is taken up by anti-fuse units increases.